'Advanced' topic: outdoor frag tanks using just sun light

[guserto4]

I have read in the past some accounts of people experimenting with relying on just sunlight for coral growth. I am relocating to Los Angeles in the spring and am interested in doing a frag tank on a balcony or deck to take advantage of Southern California's sunshine and would like to hear people's success & failures setting something up outdoors using only natural light. Assuming you live somewhere with ample sun and appropriate outdoor winter temperatures, how well does the sun grow your corals and what problems (lighting or otherwise) did you run into having a tank outside?

I understand there is likely to be greater potential for algae, but has anyone used a treated pane of glass for a top to cut down the amount of light that enters the water? Seems like buying a specially coated glass topper is cheaper than buying lights and ongoing electricity to run them.

Thoughts or experiences?

 

[Bryopsis]

Can't say I've had any experience with this as I don't own my own house yet, but I saw a frag business, can't recall the guys name. He had a greenhouse dedicated to it. The thing he did say was that he had to compensate more than he thought for the sun via lights. I think that was the big thing I took away from his little scpheel..

Otherwise this is something that would be great. I have used a window before which worked fairly well minus the algae, but being here in the Midwest, the sun is pretty short in the winter..

 

[Subsea]

Heat gain

Heat gain

I have read in the past some accounts of people experimenting with relying on just sunlight for coral growth. I am relocating to Los Angeles in the spring and am interested in doing a frag tank on a balcony or deck to take advantage of Southern California's sunshine and would like to hear people's success & failures setting something up outdoors using only natural light. Assuming you live somewhere with ample sun and appropriate outdoor winter temperatures, how well does the sun grow your corals and what problems (lighting or otherwise) did you run into having a tank outside?

I understand there is likely to be greater potential for algae, but has anyone used a treated pane of glass for a top to cut down the amount of light that enters the water? Seems like buying a specially coated glass topper is cheaper than buying lights and ongoing electricity to run them.

Thoughts or experiences?[/QUOTE

Before you concern yourself with the Reds and the yellows in the light spectrum, with your filters, you will need to remove heat gain.
If you cover tank, then invite people over for the shrimp boil, because the water is going to get hot.
Patrick

 

[Coelli]

Contact o2manyfish here on RC - he has an outdoor tank and I think he said has had as many as 4. It's plumbed into his main system. No cover, but he uses a fan for cooling and said on some days there can be as much as 50g a day in evaporation. He's in a hot part of LA though. Do you know which part you're relocating to? There can be as much as 10-15 degrees difference depending on where you are.

Addit: maybe a mod could move this to the SoCal subsection?

 

[Bryopsis]

Holy crap that's a lot of evap... :|

 

[guserto4]

Wow, that's a lot of evaporation! No wonder there's a drought! I'm not sure where I'll end up, but our LA office is in the financial district so Ive been contemplating a loft somewhere nearby. I'll PM o2manyfish. He's gotta be a little inland for that kind of evap. With the weather you've been having in SoCal (I hear the whining everyday from my coworkers in San Diego), a chilling system would also certainly have to be in play. I wonder what's cheaper, powering lights and a chiller inside or a chiller for the outside...

 

[Subsea]

I evaporate > 100GPD. I suggest you consider keeping your tanks inside. If you want natural light, consider using fiber optics and bring it into your living space.
Patrick

 

[Timfish]

One idea I've played with but still haven't got around to actually trying is a green house with multiple layers of one of the Polygal multiwall products. The different products have different degrees of light loss so and different R values. Just playing with numbers in my head it should be feasable to build a small green house or maybe a "potting shed" that would reduce the sun to acceptable PAR levels during the day and still have a roof that has 6, 7 or 8 R rating providing some insulation in the winter nights when heating would be required. Some additional lighting probly would be needed. To help control condensation in the winter heat the space instead of the water, if the water is warmer than the air above it evaporation will increase dramaticly. Of course evaporation would be the ideal way to cool the water in the summer.

 

[GreshamH]

O2many (Dave) is a good one, as is Steve Garrett at http://www.garretts-acropolis.com/

 

[o2manyfish]

Hey Folks, I have had tanks setup outside for over 10 years now. I tried it for business purposes and found that to be no fun, and for the past 8 years have done it purely for fun. Growing corals in direct sunlight is great. The growth is easily 3-4x faster than conventional lighting methods. The colors on most corals under the sunlight is much better. The colors that you get under sunlight are significantly different.

My outdoor frag tanks have always been part of my complete system. I currently have 1100g in my system. Part of that is a 140g frag tank, and a 250g rock sump that are both outside and uncovered. I have found that evaporative cooling is efficient, and replacing all that water with Kalkwasser is huge benefit to the corals.
The most frequently asked question is, "What do you do when it rains?". And the answer is the corals are already wet so they dont mind

The truth is with 1100g of water, and only about 24 sq feet of exposed surface area, when we get in So Cal it's not enough to make much change. And even on a rainy day with the amount of exposed surface area I have I still evaporate out a good quantity of water.

I am located in the San Fernando Valley, so I am about 15 Miles North East of the Financial district and 25 miles north of LAx - I am by no means out in the boonies.

Steve Garrett is another great example. Steve's outside system is larger than mine, and he is a successful commercial farmer with his system. His system is covered, and over the years he has used different colors and degrees of coverage over his system.
Steve's coral colors are much more representative of what the corals will look like under conventional lighting. And in fact Steve's corals once you get them color up even better under conventional lighting. Steve's got a great selection and I eagerly collect his corals when he is at the local swaps.
My direct sunlight gets some crazy colors out of corals, but those corals can't always be maintained under conventional lighting. But what I do mainly is get the brown acros, that are doomed to never be sold and put those outside. Sometimes they color up within 3-5 days. Sometimes it takes a few weeks. But over 90% of the brown corals I bring home color back up.
In addition, the health of my fish in the outdoors tanks is amazing. while the outdoor tanks are connected to the inside tanks, I don't specifically feed the other tanks. But the fish out there are amazing. I recently added several Juvenile Chevron tangs with advanced HLLE, and within a couple of weeks they were healed up and ready to find new homes.

Dave B

 

[Benar]

I've been wondering about doing the same here in New Zealand. Just curious about our sunlight strength here, our ozone layers is one of the thinnest so UV would be heavy. We also get days-up to a week of cloudiness a few times a year. Temp averages about 24 (~75 F) in summer, 15 (~60? F) in the coldest months. There's also that other hurdle to get over... The fiancé.

 

[uwiik]

I have been using natural sunlight all my life due to profession...Outdoor sunlight is off course the best light you can get, no artificial light can compare to natural sunlight in coloring up the corals...BUT you must have some kind of filter to filter the sunlight and get the color that you want, unless you are growing SPS only you must have many many different tubs with different sunlight filter on top of the tank. Don't forget corals come from so many different depth in the sea, not all corals will fare well under unfiltered natural sunlight...

 

[BrentH]

Nice thread I'm in SoCal also and have thought of plumbing a tank from my current 500 to a frag tank outside I'm going to Steve garrets tomoroe see how it goes thanks o2many fish for the explanation u have to be a true fish guy to do outdoor

 

[callsign4223]

Quick question on this.

Could you put the tank in an enclosed porch right next to a south facing window? Would the windows filter out all the important wavelengths or would it work and you could then climate control the area and not have to worry about evap and temp?

 

[guserto4]

That's what I've been thinking about- if it's a greenhouse, what's the window coating difference vs a window in a house? I don't know much about greenhouses, but I think the "newer" house windows cut down or out the UV light. So more for algae, less for corals. Unless you have an old window, then it's just about refraction, intensification, etc. because of the angles.